检索结果-南通市图书馆

西藏雄村矿区1号矿体黄铁矿标型特征及其地质意义

在线全文

学校读者我要写书评

暂无评论

矿物岩石地球化学通报 2024年第2期43卷 372-386页

作者：吴昌益郎兴海张赫王旭辉张鹏邓煜霖娄渝明姜楷成都理工大学地球科学学院成都610059 四川省国土科学技术研究院成都610074 西藏天圆矿业资源开发有限公司西藏日喀则857000

为研究西藏雄村矿区黄铁矿的成因矿物学和找矿矿物学意义,本文对雄村矿区1号矿体主成矿阶段的黄铁矿开展了X射线衍射、热电性、电子探针和LA-ICP-MS分析。结果表明,1号矿体黄铁矿晶胞参数a0为5.41438×10^(-10)~5.41966×10^(-10)m,平均... 详细信息

为研究西藏雄村矿区黄铁矿的成因矿物学和找矿矿物学意义,本文对雄村矿区1号矿体主成矿阶段的黄铁矿开展了X射线衍射、热电性、电子探针和LA-ICP-MS分析。结果表明,1号矿体黄铁矿晶胞参数a0为5.41438×10^(-10)~5.41966×10^(-10)m,平均Δa0值为5.41747×10^(-10)m;体积V为158.7190×10^(-10)~159.1946×10^(-10)m^(3),ΔV平均值为158.9896×10^(-10)m^(3);热电系数α为-336.7~330.6μV/oC。黄铁矿S含量为51.34%~53.44%,平均值为52.92%;Fe含量为44.06%~46.90%,平均值为46.18%,Co/Ni值集中在10附近。结合前人研究成果,我们认为1号矿体主成矿阶段的黄铁矿为岩浆热液成因,主要为N型黄铁矿,形成于硫逸度较低的中高温环境。另外,黄铁矿不是1号矿体的主要载金矿物,预测该矿体处于成矿系统的中下部,在深部具有一定的延伸趋势,但是很可能被后期侵位的黑云母花岗闪长岩破坏,深部找矿潜力不大。

关键词：西藏雄村矿区黄铁矿晶胞参数热电性斑岩型矿床

同方期刊数据库

数字经济促进乡村产业振兴的影响机理及实证研究

在线全文

学校读者我要写书评

暂无评论

江南大学学报（人文社会科学版） 2024年第1期23卷 37-51,59页

作者：鲁钊阳杜雨潼邓琳钰西南政法大学经济学院重庆401120 西南大学经济管理学院重庆400715 西南政法大学商学院重庆401120

在弄清楚数字经济促进乡村产业振兴机理的基础上,文章基于2013—2020年中国省级面板数据,实证分析数字经济对乡村产业振兴的影响。研究结果显示,数字经济有效促进了乡村产业振兴,主要表现在数字产业化对农业产品产业体系的促进作用和产... 详细信息

在弄清楚数字经济促进乡村产业振兴机理的基础上,文章基于2013—2020年中国省级面板数据,实证分析数字经济对乡村产业振兴的影响。研究结果显示,数字经济有效促进了乡村产业振兴,主要表现在数字产业化对农业产品产业体系的促进作用和产业数字化对农业支撑产业体系的促进作用两个方面,并且这种促进作用在高数字经济水平、低乡村产业振兴程度的地区表现得更为显著。进一步分析表明,数字经济通过促进产业结构转型升级进而推动乡村产业振兴,数字经济的影响具有微弱的空间溢出效应。

关键词：数字经济乡村产业振兴数字产业化产业数字化乡村振兴

The Impacts of Simulated Microgravity on Rat Brain Depended on Durations and Regions

在线全文

学校读者我要写书评

暂无评论

Biomedical and Environmental Sciences 2019年第7期32卷 496-507页

作者： CHEN Bo ZHANG yu Shi LI George CHO Jun-Lae deng yu lin LI yu Juan School of Life Science Beijing Institute of Technology Beijing 100081 China Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Beijing 100700 China Faculty of Pharmacy The University of Sydney Sydney 2006 NSW Australia

Objective To explore the dynamic impacts of simulated microgravity(SM) on different vital brain regions of rats. Methods Microgravity was simulated for 7 and 21 days, respectively, using the tail-suspension rat model. Histomorphology, oxidative stress, inflammatory cytokines and the expression of some key proteins were determined in hippocampus, cerebral cortex and striatum. Results 21-day SM decreased brain derived neurotrophic factor and induced neuron atrophy in the cerebral cortex. Strong oxidative stress was triggered at day 7 and the oxidative status returned to physiological level at day 21. Inflammatory cytokines were gradually suppressed and in striatum, the suppression was regulated partially through c-Jun/c-Fos. Conclusion The results revealed that the significant impacts of SM on rat brain tissue depended on durations and regions, which might help to understand the health risk and to prevent brain damage for astronauts in space travel.

关键词： Microgravity Brain Neuron atrophy Oxidative stress Inflammatory cytokines

Synthesis of Nitroanilines Catalyzed by Horseradish Peroxidase in the Presence of NaNO2 and H2O2

在线全文

学校读者我要写书评

暂无评论

Chemical Research in Chinese Universities 2013年第6期29卷 1164-1166页

作者： LIU Cong DAI Rong-ji lin Jie SUN Jian-hua CHEN Shi deng yu-lin School of Life Science Beijing Institute of Technology Beijing 100081 P.R.China

The synthesis of nitroanilines catalyzed by horseradish peroxidase（HRP） in the presence of sodium nitrite and hydrogen peroxide was investigated, o-Nitroaniline and p-nitroaniline were found in the nitrated products. 2-Aminotoluene and 4-aminotoluene could also be nitrated to give corresponding nitrated products. This protocol has great potentials to open new avenues useful for the synthesis of nitroaniline and its derivatives.

关键词： Nitroaniline Horseradish peroxidase Phenylamine Nitration Enzyme

Separation of non-denatured proteins using semi-crosslinked polyacrylamide capillary gel electrophoresis

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Beijing Institute of Technology 2014年第1期23卷 131-137页

作者： XU Jian-dong HU Ding-yu BAKTUR Rena GENG Li-na deng yu-lin School of Life Science Beijing Institute of Technology Beijing 100081 China State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China The Chinese People's Armed Police Force Academy Langfang Hebei 065000 China

This work presents an approach to build a high-performance, low-viscous and replaceable separation matrix, semi-crosslinked polyacrylamide （semi-CPA） capillary gel electrophoresis. Non- denatured basic proteins, such as lysozyme, cytochrome C, ribonuclease A and trypsin were separa- ted. The impacts of monomer and cross-linker concentrations on protein separation were studied, and the ability of dynamic capillary inner wall coating was demonstrated. The UV absorption interfer- ence by semi-CPA gel matrix was successfully overcome by a partial filling technique, which results in sensitivity 20 times higher than other protein separation method. The excellent separation ability, reproducibility and dynamic coating ability made semi-CPA an ideal separation media in both capillar- y electrophoresis and microfluidic chip separation scheme.

关键词： capillary gel electrophoresis semi-crosslinked polyacrylamide (semi-CPA) non-dena-tured protein separation

Dynamic analysis of beta oscillations in Parkinsonian neural networks with the pedunculopontine nucleus under optogenetic control

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2024年第6期40卷 125-140页

作者： yuzhi Zhao Honghui Zhang Ying yu lin Du Zichen deng School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an710072China School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China

Clinical experiments have proven that the pedunculopontine nucleus(PPN)plays a crucial role in the modulation of beta oscillations in Parkinson’s disease(PD).Here,we propose a new computational framework by introducing the PPN and related synaptic connections to the classic basal ganglia-thalamo-cortical ***,the improved model can not only simulate the basic saturated and beta activities mentioned in previous studies but also produce the normal alpha rhythm that is much closer to physiological ***,the results show that Parkinsonian oscillation activities can be controlled and modulated by the connection strength between the PPN and the globus pallidus internal nucleus(GPi)and the subthalamic nucleus(STN),supporting the fact that PPN is overinhibited in ***,the internal mechanism underlying these state transitions is further explained from the perspective of ***,both deep brain stimulation(DBS)and optogenetic technology are considered effective in terms of abnormal *** when a low-frequency DBS is added to the PPN,beta oscillations can be suppressed,but it is excited again as the DBS’s frequency gradually increases to a larger *** results coincide with the experimental results that low-frequency stimulation of the PPN is effective,and verify the rationality of the ***,we show that optogenetic stimulation of the globus pallidus external(GPe)expressing excitatory channelrhodopsin(ChR2)can effectively inhibit beta oscillations,whereas exciting the STN and PPN has a limited *** results are consistent with experimental reports suggesting that the symptoms of PD’s movement disorder can be alleviated under the GPe-ChR2,but not STN-ChR2,*** the functional role of the PPN and the feasibility of optogenetic stimulation remain to be clinically explored,the results obtained help us understand the mechanisms of beta oscillations in PD.

关键词： Pedunculopontine nucleus Beta oscillations Optogenetic Deep brain stimulation Parkinson’s disease

Broadband angular spectrum analog processors based on all-dielectric metasurfaces

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 188-190页

作者： lin deng Yongmin Liu Department of Electrical and Computer Engineering Northeastern UniversityBoston 02115USA Department of Mechanical and Industrial Engineering Northeastern UniversityBoston 02115USA

Digital signal processors are extensively used to execute mathematical operations and advanced computational tasks on digital ***,they suffer from several inherent limitations,including low speed,high energy consumption,and large memory requirements,because of the hardware bottleneck and the imperative conversion between digital and analogue signals.

关键词： dielectric spectrum hardware

同方期刊数据库

Pd Pt VO_(x)/CeO_(2)-ZrO_(2):Highly efficient catalysts with good sulfur dioxide-poisoning reversibility for the oxidative removal of ethylbenzene

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2024年第4期138卷 153-166页

作者： Jia Wang yuxi Liu Jiguang deng lin Jing Xiuqing Hao Xing Zhang Xiaohui yu Hongxing Dai Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaLaboratory of Catalysis Chemistry and NanoscienceDepartment of Chemical EngineeringFaculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

The PdPtVO_(x)/CeO_(2)-ZrO_(2)(PdPtVO_(x)/CZO)catalysts were obtained by using different approaches,and their physical and chemical properties were determined by various *** activities of these materials in the presence of H_(2)O or SO_(2)were evaluated for the oxidation of ethylbenzene(EB).The PdPtVO_(x)/CZO sample exhibited high catalytic activity,good hydrothermal stability,and reversible sulfur dioxide-poisoning performance,over which the specific reaction rate at 160℃,turnover frequency at 160℃(TOF_(Pd or Pt)),and apparent activation energy were 72.6 mmol/(g_(Pt)·sec)or 124.2 mmol/(g_(Pd)·sec),14.2 sec^(-1)(TOF_(Pt))or 13.1 sec^(-1)(TOF_(Pd)),and 58 k J/mol,*** large EB adsorption capacity,good reducibility,and strong acidity contributed to the good catalytic performance of PdPtVO_(x)/*** activity of PdPtVO_(x)/CZO decreased when 50 ppm SO_(2)or(1.0 vol.%H_(2)O+50 ppm SO_(2))was added to the feedstock,but was gradually restored to its initial level after the SO_(2)was cut *** good reversible sulfur dioxide-resistant performance of PdPtVO_(x)/CZO was associated with the facts:(i)the introduction of SO_(2)leads to an increase in surface acidity;(ii)V can adsorb and activate SO_(2),thus accelerating formation of the SO_(x)^(2-)(x=3 or 4)species at the V and CZO sites,weakening the adsorption of sulfur species at the PdPt active sites,and hence protecting the PdPt active sites to be not poisoned by SO_(2).EB oxidation over PdPtVO_(x)/CZO might take place via the route of EB→styrene→phenyl methyl ketone→benzaldehyde→benzoic acid→maleic anhydride→CO_(2)and H_(2)O.

关键词： Ceria-zirconia Supported palladium-platinum-vanadium catalyst Volatile organic compound Ethylbenzene oxidation Sulfur dioxide resistance

Effect of nano-graphite on mechanical properties and oxidation resistance of ZrB_(2)-SiC-graphite electrode ceramics

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第6期31卷 1502-1513页

作者： Bo-lin Yang Chang-liu Kuang Zheng-long Liu Chao yu Cheng-ji deng Jun Ding The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

ZrB_(2)-based ceramic composites were prepared by spark plasma sintering using ZrB_(2) powder prepared by molten salt method as raw material and SiC and nano-graphite as *** effects of nano-graphite addition on the physical properties and oxidation resistance of ZrB_(2)-based ceramic samples were *** results show that the addition of an appropriate amount of nano-graphite can effectively improve the density of ZrB_(2)-based ceramic composites and improve the physical properties of the *** flexural strength of the ceramic sample with 8 vol.%nano-graphite reached 418.54 MPa,which was 53.14% higher than that of ZrB_(2)-SiC ceramic material(273.31 MPa),and its oxidation resistance was also significantly *** demonstrats that the addition of an appropriate amount of nano-graphite can effectively improve the physical properties and oxidation resistance of ZrB_(2)-SiC ceramic *** prolonging its service life in application and promoting the development of ZrB_(2)-based ceramic composites,it is of great significance for clean steel smelting.

关键词： ZrB_(2)-SiC-graphite electrode ceramic ZrB_(2)-based ceramic composite Nano-graphite Physical property Oxidation resistance